Safety guard for machine presses



Oct. 7 1924.

H. DOERSAM SAFETY GUARD FOR MACHINE PRESSES Filed Aug. 23. 1923 W 9 m fV M 1 :0 0 m w H a, w A: m a Q z z A TTORNE Y Patented Get. 7, 1924.

PATENT OFFICE.

HUGO IDOERSAM, OF NEW YORK, N. Y.

SAFETY GUARD FOR MACHINE IPBESSES.

Application filed August 23, 1923. Serial No. 658,883.

T 0 all whom it may concern:

Be it known that I, HUGO DOERSAM, a citizen of Germany, and resident ofNew York, in the county of New York and State of New York, have inventedcertain new and useful Improvements in Safety Guards for MachinePresses, of which the following is a specification.

The main object of this invention is to provide a device to be attachedto a punch press to sweep the area above the die for the purpose ofremoving the fingers from beneath the same, so that no injury may 001cur if the operator fail to remove his fingers.

Another object is to provide a safety device as mentioned which isoperated simultaneously with the tripping or release of the punch pressclutch and performs its function before the ram begins its descent,thereby allowing the device ample time in which to remove the fingersfrom between the punch and die.

These and other objects will become apparent in the description below,in which characters of reference refer to like-named parts in thedrawing.

Referring briefly to the drawing, Figure 1 is a front elevational viewof the device.

Figure 2 is an end elevational view of the same.

Figure 3 is a sectional end elevational view of the device taken on line3-3 of Figure 1.

Figure 4 is a side elevational view of the cam plate.

Figure 5 is a front elevational view of the same.

Figure 6 is a partly sectioned elevational view of the gear carryingyoke.

Figure '7 is a front elevational view of a punch press. showing thesafety device applied thereto. 1

Referring in detail to the drawing, the numeral 10 indicates the legstands of a punch press upon which the table 11 is mounted, the lattersupporting the die 12. The crank shaft 13 at the upper end of the presshas a fly wheel 14 at one of its ends and is connected to aram 16 by aconnecting rod 15, the ram being slidable behind the guides 17 A bracket18 is preferably attached to the left guide at its lower end, saidbracket projecting outwardly and having a bifurcated en 8 in w ch a ho eis formed, the latter receiving a sleeve 20. One end of the sleeve has aU-shaped yoke 21 fixed thereto, the arms 22 of the yoke having holestherein in which a shaft 24 is rotatably mounted. The bifurcated end ofthe bracket has a screw 25 mounted therein which rigidly secures thesleeve 20 in place in the bracket 18.

A spindle. 26 having a sector gear 27 mounted on the end between thearms 22 of the yoke, is rotatably mounted in the sleeve 20. The sectorgear 27 meshes with a small pinion 28, the latter being mounted on theshaft 24 above the lower arm 22. The opposite end of the spindle 26 hasa bell crank 29 secured thereon by a screw 30. The vertical arm of thebell crank has a pin 31 projecting from its side, the purpose of whichwill be more fully hereinafter described, and the opposite arm has oneend of a rod 32 connected thereto, the lower end of the latter beingattached to the foot trip lever 33/ An angular support 34 risesvertically from the bracket 18 and has a spring 35 secured thereto, thelatter being attached to the bell crank 29. A collar 36 having anextension 37, is mounted on the sleeve 20 and has a screw 38 whichsecures said collar in any desired position. A relatively long sweeperblade 39 having a hole at one end which is slipped over the shaft 24, ismounted on said shaft and is secured in place by a screw 40.

The entire device thus far described is fixed as stated to the leftslide guide 17 and is actuated by the rod 32. An additional means foroperating the bell crank 29 is provided and comprises a longitudinalbracket 41, the latter being secured to the ram 16. Guide ridges 42 areformed on the face of said bracket. Between these ridges the arm 43 of acam plate 44 is slid. said arm having a slot 45 therein thru which ascrew 46 passes, said screw engaging the bracket 41 and permittinglateral adjustment of the blade 44.

The primary purpose of the entire device is to prevent accidents whichwould occur when the operator places the Work in the gage of the die andby mistake places it in wrong position and tries to save the blank bythrusting his fingers between the punch and die, from which seriousinjury usually results. The blade 39 is provided to prevent the peratorfr m being able to place shaft clutch is released, thus permittingrotation of the crank shaft 13- and lowering of the. ram 16.Simultaneously, the rod 32 on the opposite side of the press is loweredand rotates the bell crank 29 until the screw 80 comes into contact.with the extension. 3 7

of the collar 3.6. As the bell crank isirigidly secured to the spindle26, the; latter will. rotatethe. sector gear 27 which rotates the pinion28, and consequently,the shaft E, there by swinging: the sweeping blade.39: ab ove'the die thrn an arc, carrying everything before it. from thesurface of the die. When the stroke of the ram-16} completed, the bellcrank will be rotated to its, original position by the tension of spring35.

, tion' in the usual manner.

It sometimes: occurs that a punch press gets out of order because thebrake becomes loose, permitting the crank s-haftto rotate of its ownaccord;.o-r the clutch may break,

' or the fly wheel be locked on thecrank shaft owing to lack oflubrication. This device will operate just as well under all suchconditions. The greatest danger: with punch presses is; that they mayoften repeat their operations of their own accord. As a punch pressrepeats, the rod 32: is useless and therefore will not operate the: bellcrank 29 owing to said rod, being in its. lowered position.Toi'rotatethe bell crank, the cam plate 44- is provided. As the ramdescends-v when repeating, thelower angular edge of the cam plate 44:Wlll engage the pin 31. on.

the bell crank 29 and will rotate the latter,

causing the spindle 26" and shaft 34 to func- Frorn this description itis obvious that if the release rod 32 is broken, the cam plate l l willoperate the bell crank to prevent injury to the operator.

Another feature of this device is the mounting of the yoke and sleeveso'th-at. they maybe readily rotated out of position, as is requiredwhen a die-setter is removing or interchanging dies. The yoke may be;readily tilted to any. angle desired by; loose'ninq the screw 25. at thebifurcated ends. of. tire bracket 18, after which the sleeve may be.readily rotated out of position.

- v 1. A device of the class described commounted in said yoke, means;at the lower.

end of said. shaft for sweeping the region above a die, and means for"rotating. said shaft.

2. A device of the class described comprising a bracket adapted to befixed to a punch press and having a bifurcated end, a sleeve mounted insaid bracket, Ushaped yoke fixed to one end of said sleeve, a shaftpassing thru the arms of said yoke, a sweeper blade at the lower end ofsaid shaft, a gear on said shaft, and means for rotating said gear. 3. Adevice of the class described comprising a bracket adapted to be fixedto a punch press, a sleeve passing thru said bracket and having aU-shaped yoke at one of its ends, a shaft rotatablymounted; said yoke,asweeper blade at the lower end ofsaidv shaft, a gear: on said shaft, aspindle mounted insaid sleeve, a sector" gear "on one end of saidspindle meshing with theaterssaid gear, and means for rotating saidspindle,

42. A device of the class described com-- prising a bracket adapted tobe fixed to a punch press, a sleeve passing thru said bracket and havinga u shaped yoke at one of its: ends,.-a shaft: rotatably mounted in saidyoke, a sweeper blade at-the lower end of said sha.-ft,.a gear on saidshaft, arspiindle moiurtedin said sleeve, a sector gear on one end Offsaid spindle meshing with the aforesaid gear, a bell crank: at theopposite-end of said spindle, and means for rotating said" bell crank torotate said. shaft 5. A device of the class describedcom prising abracketadapted: torbe fixed to a punch press, a sleeve passing :thrusaid bracket and having a U-shaped yoke-- at. one;

of its ends, a shaft rotatably mounted in said yoke, a sweeper blade atthe lower end.

of said shaft, agear on. said shaft, a spindle mounted in said; sleeve,a sector gear onone end of said spindle meshing with the aforesaid gear,a bell crank at the; opposite end of said spindle, a pinonsaidbell'cranhxa plate secured to tl ieareciprocating rain adjacentsaid pin, said cam plate vbeing adapted to rotate. said spindle, meansfor returning said crank to the original position.

6. A device of the class described comprising a bracket adapted to. befixed to a punch press, a sleevev passing thru said bracket and having aU-shaped yoke at. one of its ends, a shaft rotatably mounted.

said yoke, a sweeper blade at. the. lower end of said.- shaft, a. gearon said shaft, a spindle mounted in said; sleeve, a sector gear on oneend of said spindle: meshing with. the aforesaid gear, a bell crank: atthe opposite end of said spindle, a pin on said bell crank, a cam platesecured to the reciprocating rain adjacent said pin, said cam plate]being; adapted to rotate said spindle when. engag ingsaid pin, anangular support projecting y from said bracket, a springfsdspended said.support and secured to one-- arm efisaid bell crank, said, being.adapted ta return the bell crank to normal position after the latter hasbeen rotated, and means for limiting the rotation of the bell crank.

7. A device of the class described comprising a bracket adapted to befixed to a punch press, a sleeve passing thru said bracket and having aU-shaped yoke at one of its ends, a shaft rotatably mounted in saidyoke, 21- sweeper blade at the lower end of said shaft, a gear on saidshaft, a spindle mounted in said sleeve, a sector gear on one end ofsaid spindle meshing with the aforesaid gear, a bell crank at theopposite end of said spindle, a pin on said bell crank, a cam platesecured to the reciprocating ram adjacent said pin, said cam plate beingadapted to rotate said spindle, an angular support projecting from saidbracket, a spring suspended from said support and secured to one arm ofsaid bell crank, said spring being adapted to return the bell crank tonormal position after the latter has been rotated, a collar on saidsleeve, an extension on said collar above the bell crank, said extensionbeing adapted to engage the sides of the bell crank to limit rotation ofthe latter, and means for rotating said bell crank.

Signed at New York, in the county of New York and State of New York,this 7th 30 day of August, A. D. 19:23.

HUGO DOERSAM.

